Detection rules › Sigma

Suspicious Dropbox API Usage

Severity
high
Author
Florian Roth (Nextron Systems)
Source
upstream

Detects an executable that isn't dropbox but communicates with the Dropbox API

MITRE ATT&CK coverage

TacticTechniques
Command & ControlT1105 Ingress Tool Transfer
ExfiltrationT1567.002 Exfiltration Over Web Service: Exfiltration to Cloud Storage

Event coverage

ProviderEvent IDTitle
Sysmon3Network connection

Stages and Predicates

Stage 1: selection

or:
DestinationHostname|endswith: api.dropboxapi.com
DestinationHostname|endswith: content.dropboxapi.com
Initiated: true

Stage 2: not 1 of filter_main_legit_dropbox

Image|contains: '\Dropbox'

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

FieldKindValues
DestinationHostnameends_with
  • api.dropboxapi.com
  • content.dropboxapi.com
Imagematch
  • \Dropbox
Initiatedeq
  • true corpus 40 (sigma 40)